Neuropathic pain would mean that he could chop his entire body off, he would still feel the pain, iyswim.
It is real damage that causes 'phantom pains', sometimes totally unrelated to the original injury. The spinal block he wants implanted may also be useless to him.
I titrated a few tricyclic antidepressant for my neuropathy, many years ago. But the dose that took the pain away also took me away, so I stopped and put up with the pain, still do.
Sadly for him things will not improve, or at least not go away, he cannot necessarily be cured, though he may yet find a medication combination that will suit him.